#include <string.h>
#include <stdio.h>
#include <stdlib.h>

int st(char[]);

int main()
{
    char s[] = "Good Afternoon!";
    printf("%s\n", s);
    st(s);
    printf("%s\n", s);
    system("pause");
    return 0;
}

int st(char s[])
{
    strcpy(s, "How are you?"); // 改变字符数组内容
    return 0;
}